Police said Vanderhall went to his mother’s home on Perry Street in Hempstead around 1:30 a.m. Saturday and became enraged when he found the door was locked.

Vanderhall then allegedly went into the garage and grabbed a hammer before entering the home through the basement, according to police.

After forcing his way into the house, police said Vanderhall bludgeoned his mother to death before proceeding up the stairs and doing the same to his sister. Police said he struck and killed Simpson once he got upstairs.

Vanderhall allegedly bludgeoned another one of his sister’s friends — 29-year-old Candace Murray — but she managed to fight back and escape the home.

Murray’s relative told CBS2 she is traumatized but recovering from her injuries.

“She’s in the hospital right now. She’s alright though, she’ll be fine,” he said.

Vanderhall fled the scene, but was found inside a parked car on private property a few miles away from his mother’s home. He was charged with three counts of murder and one of attempted murder.

Police said the hammer was recovered at the scene.

Relatives of the victims told CBS2 they were overwhelmed the loss and struggling to process the violence that turned a tidy residence into a house of horrors.

“Beautiful, outstanding people,” cousin Juanita Johnson said.

Lynn spent decades teaching children at daycare. Melissa worked as a physician’s assistant.

“We are all in a state of shock,” Family & Children Association President/CEO Dr. Jeffrey Reynolds said. “This is a devastating loss for FCA and a devastating loss for the thousands of struggling families in Hempstead who have benefitted from Lynn’s passion, dedication and three decades of community service. To say that we will miss her dearly would be an understatement.”

Simpson’s father, Denis, said he’s now trying to stay strong in his daughter’s memory.

“You have to wonder, why did this happen? They didn’t give problems, these girls don’t give problems,” he told CBS2’s Ali Bauman.

Denis said his daughter was looking forward to an upcoming trip to Cuba.

“Her smile, her love, she was so protective of me,” Simpson’s mother, Wendy, added.

Relatives said Vanderhall was a friendly and athletic kid, but as an adult he suffered mental illness, which apparently got worse several years ago after the sudden death of his father, CBS2’s Jessica Borg reported.

Friends said his mother endured chilling run-ins with her son, which they described as out-of-control.

“She had always been there for him, being a loving mother, making sure he gets help and everything,” Johnson said. “She did her best.”

Domestic disturbances between the two brought people to the home at least twice in the past. Lynn obtained an order of protection against Vanderhall earlier this year, according to police.

Vanderhall’s criminal record included arrests for DWI and another for sexual abuse.

He was homeless after his mother kicked him out of the home on Perry Street, according to police.